The knobs are especially difficult to use (on desktop here). The first two knobs only respond to click & vertical drag - moving up rotates clockwise, moving down rotates ccw. Moving left or right does nothing. The second knob's grab handle is just totally wrong, appearing in only about the 4 o'clock to 6 o'lock position.

Round knobs are just a terrible idea. They never work comfortably with a mouse or touchpad, and are often an accessibility challenge.